The primary objective of the proposed workshop is to provide an intense dialogue of the fundamentals, state-of-the-art advances and major gaps in the cell and molecular biology of drug addiction. Targeted to new or experienced investigators, the workshop will combine formal presentations and informal discussions to convey the merits and excitement of cellular and molecular approaches to drug addiction research. The workshop will stress the significance of this approach not only to the most costly neuropsychiatric disorder, addiction, but its applicability to learning, memory, neurochemical correlates of reward, perception and other disciplines of neuroscience. Research of the molecular and cellular changes that occur in response to drugs is critical for clarifying whether adaptive processes are diverse for each stage of addiction and for each drug of abuse. With the advent of genomics and proteomics, an extraordinary opportunity now exists to develop comprehensive models of neuroadaptative processes fundamental to addiction, craving, and relapse to drug use. The workshop will provide attendees with a spectrum of disciplines that can contribute to developing comprehensive models of each stage of drug addiction. The following disciplines will be presented: 1. an overview of addiction; 2. the contribution of noninvasive brain imaging to identifying drug targets and adaptive processes; 3. the association between neuroadaptative processes to drugs and behavioral manifestations; 4. linking genotype to drug response; 5. tolerance sensitization and adaptation at the cellular level; 6. regulation of receptor, enzyme function and associated neural activity. This workshop will provide an integrated view of current and novel research on neuroadaptive responses to addiction, foster discussion on collaboration and integration, provide critical information needed to construct a model of addiction as a disease and novel molecular targets for biological treatments. Beyond the plane of scientific endeavor, the information is vital for formulating public policy and for enlightening the public on the neurobiological consequences of drug use and addiction. The proposed workshop will generate intense interest in this approach, open conduits for collaborations and novel routes to investigating the neurobiology of addiction.